There is a concrete tile roof on a house i am renovating that appears to leak sometimes in a few spots. The concrete tiles appear to be in pretty good condition but there are water stains on the interior ceiling in a few places. A friend who has the same type of tiles in worse condition says his roof leaks in one spot when there is heavy wind from a particular direction- like during some typhoons- and we usually get a few typhoons every year. We are planning to redo the interior ceilings and walls (with shikkui?) and really do not want to finish them and then find out the roof leaks. Another friend who had his repainted got it done for 200,000yen. I'm guessin ours would be a little more as it's bigger. Trying to understand the options to decide if I should farm it out, do it myself or replace the roof with metal 'galbarium'(sp?). Ive been a carpenter and a painter in past lives so not too afraid of the work but I've never actually 'painted' a roof before....

So, questions:
Does anybody have any experience repainting their roof?
What kind of paint and cauld caulk (sealant?) did you use?
How long did it take?
What was the process? Pressure wash, caulk, paint, more beer?
What kind of paint?
What can possibly/probably go wrong? other than falling off? or the wife saying, "I TOLD you to have somebody do it for you!" when i make THAT mistake.

The only advice I can offer is to find a secure place to wedge the beer crate and maybe lay a few old mattresses down below the area you are working in case of a sudden unexpected descent from the roof

We have galvanium on both the house and cafe roof and it seems ok, doesn't need any maintenance and it's easy to climb up when the chimney need sweeping. Although you do need to wear tabi or soft rubber soled shoes to avoid slipping. If you do go down the route of replacing the roof it might be worth looking into incorporating an ECS or OM Solar system into the house. It's free heating in the winter and cools the house during the summer but much depends on what level of insulation you have. With a bit of sunshine on a winter's day the inside of our house can easily get up to the mid 30's.

I am in the same situation myself right now and pricing out different options.
How big is the roof?

If you replace the tile with a steel roof or asphalt shingles,
It will be seismically speaking far safer.

If you decide to stick with the concrete and paint it the materials are very cheap. So DIY will cost very little for paint.
Scaffolding and labor are what put the prices up.
Basic process is:
First pressure wash, replace broken tiles. Then you need to grout the tiles at certain points like the ridges. You need to use a grout that’s softer than the tiles so that it will break before the tile.
When I went to Komeri they told me I needed to first use a sealer and then paint as my tiles have no coating left at all.

Upon closer examination (of roof and personal time/energy/finance situation) and comparison with other roofs we are going to leave it as it is as it appears to have a number of years left in it (famous last words?! Or a chicken out due to the fact that said painting would have to be done in the dead heat of summer?). I like the metal roof idea and plan to use that on the addition going on the back side. I'm hoping that will be a good chance to hone my skills for it and when I have to do the whole roof in a few years. I was also overwhelmed by all the different types of roof tile paint. The types that reflected infrared rays looked like a good choice as there is a lot of exposure to the sun and summers are hot and humid here.